The present invention relates generally to magnetic device structures. More particularly, the present invention relates to systems and methods for mounting and locking magnetic devices on printed circuit boards. Even more particularly, the present invention relates to a bobbin leg configuration permitting surface mounting of magnetic devices to the underside of printed circuit boards configured to receive them.
Designers of magnetic devices such as transformers or inductors were at one time primarily concerned with core material and size. In recent years however, mounting and packaging have become progressively more important with regards to the ability of the magnetic devices to be efficiently mounted on a printed circuit board. This ability directly relates to the total cost of the component, as space on such boards is generally limited. As the packaging or housing sizes for electronic apparatuses also become smaller and flatter, the height of the magnetic components on printed circuit boards also becomes critical. Rework, inspection and production costs are also relevant factors that must be considered in magnetic device design.
On single sided printed circuit boards, the larger components are placed on the top side of the board (generally the side with no pads or traces). The surface mount parts which are normally small are placed on the bottom side of the printed circuit board (generally the side with pads and traces). Placing a larger surface mount magnetic component on the bottom side of the printed circuit board would greatly increase the height of the assembly, which is undesirable.
It is desirable, therefore, to provide a magnetic device assembly that would allow for placement of the large portion of a magnetic device on the top side of a printed circuit board while the surface mount solder joint is made to the bottom of the printed circuit board.